Does Sony delete non-active accounts?

I have a few account that I have forgotten the passwords to over the years. When my Playstation 3 broke I bought an Xbox to try it out, using my same name as from Psn. With the next gen announces I'm going to be switching back to psn and have run into a problem. I will not be able to use my name unless the account is deleted. So, after a certain amount of time non-active are accounts deleted?